In Ministerial Ordinance Concerning Compositional Standards, etc. for Milk and Milk Products, cream is defined as a food configured such that an oil-and-fat contained in the cream has a milk fat content of 100% and there is no substitute for it in terms of good flavor and good meltability in the mouth. However, on the other hand, it has disadvantages that properties thereof are likely to be changed, it is solidified during transportation, the terminal width at the whipping is short so as to be difficult to deal with it, and further it is expensive.
At present, instead of a so-called raw cream having a milk fat content of 100%, for the purpose of utilizing the flavor and simultaneously improving workability, various types of whipped cream are available in the market, such as a type obtained by combining a milk fat and a vegetable fat with each other that is called as a compound cream, a type obtained by using only the vegetable fat that places a high value on a preserving property, a shape retaining property and a cost and that is called as a pure vegetable cream, and the like. The vegetable oil used for the starting material of the cheap pure vegetable cream has been mainly a hardened oil obtained by applying a hydrogenation process.
The hardened oil is a cheap and functional starting material, however, in recent years, it has been reported that a trans-fatty acid that occurs when hydrogenated is related to a disease such as a heart disease. In the United States and Europe, some countries take measures against it such as an obligation of labeling to food products with regard to the trans-fatty acid, and also in Japan, concerns therewith have been increased. Also, with regard to an oil-in-water type emulsion such as a whipped cream, it has been required not to use an hardened oil of a vegetable oil-and-fat containing the trans-fatty acid.
By the way, a laurin-based oil-and-fat such as coconut oil, palm kernel oil containing large amounts of a lauric acid that is a saturated fatty acid having the carbon number of 12 is known as a starting oil-and-fat material used for a whipped cream of a vegetable type called as a pure vegetable cream. The oil-in-water type emulsion obtained by using the laurin-based oil-and-fat has an extremely good meltability in the mouth, on the other hand, it has problems that emulsification is likely to be unstable, the terminal width at the whipping is short and the surface of cream whipped is likely to be roughened. Heretofore, in order to solve the problem of the laurin-based oil-and-fat, properties thereof have been improved by using a hardened oil of soybean oil, rapeseed oil or the like together. However, as mentioned above, a whipped cream that is free of trans-fatty acid has been required, thus instead of the hardened oil, a development of an oil-and-fat capable of utilizing the meltability in the mouth of the laurin-based oil-and-fat has been advanced.
As an oil-and-fat that is free of trans-fatty acid instead of a hardened oil, palm oil or a fractionated oil of palm oil is used. Palm oil maintains solid state at room temperature without hydrogenation, so that it can be used for food products in which solid fat is needed to be contained. However, palm oil has many disadvantages such that crystal grain coarsening is likely to be caused, and stability of a cream that contains the palm oil is reduced. In order to compensate for these disadvantages, a method of improving crystallinity of a palm-based oil-and-fat by applying transesterification thereto is known.
In Patent Literature 1, an oil-in-water type emulsion is disclosed, the emulsion including an oil-and-fat composition using a laurin-based oil-and-fat and a transesterified oil having a particular fatty acid composition together, being substantially free of trans-fatty acid, having a high emulsion stability, and having a good meltability in the mouth and whipping characteristics.